This invention relates to physical exercise equipment, in particular, to a novel electrical circuit which controls the output resistance of an isokinetic strength training device.
An electric generator with an electrical resistive load connected across its two ouput terminals can be used as a means for generating resistance in isokinetic exercise equipments. When the rotation speed of the generator increases, the output voltage and current raise and cause the resisting force to match the user's maximum capacity. As a result, the motion speed is limited by the user's strength. By changing the electrical resistive load, the user can change the speed limit of his motion.
Like most other isokinetic exercise equipments which utilize hydraulic cylinders as a means for generating resistance, the devices employing electric generators also suffer a major draw-back: lacking of resistance at the beginning and the end of each motion. The resistance generated by these devices increases with increasing speed of motion therefore, at the beginning and the end of each exercise repetition where the motion speed is minimal, the resistance is virtually diminished. As a result, the exercise motion does not have the pre-stretch and full range resistance which are necessary for an efficient strength training. The present invention provides a solution for the above short-coming.